Brain lipids of zitter rats with genetic spongiform encephalopathy

Brain lipids were isolated from zitter rats with genetic spongiform encephalopathy and then their composition and distribution in the brain were investigated, with particular attention to gangliosides. The cholesterol content decreased in both the cerebrum and cerebellum of the zitter rat, compared with that of SDJ rat brain as a control. Esterified cholesterol was not detected. The phospholipid content was not significantly altered. The ganglioside concentration severely decreased in zitter rat cerebrum but was almost constant in the cerebellum, compared with in SDJ rat brain. The ganglioside composition was slightly different between zitter and SDJ rat brain: the relative concentrations of GM1 and GT1b were higher, and those of GD3 and GD1a were lower in zitter rat cerebrum than in SDJ rat cerebrum. In the cerebellum, GD3, GD2 and GD1a were decreased in zitter rat brain compared with in SDJ rat brain. The long-chain base composition was not essentially different between zitter and SDJ rat brain. These findings were different from those in the cases of the brains of Creutzfeldt-Jakob disease patients and animals showing histopathologic spongiform degeneration of the brain.